function s1_goto_dir(){
cd "$1" || exit 1
}
function s2_touch_empty_file_with_given_name(){

touch "$1"
}
function s3_make_directories(){
mkdir projects
cd projects || exit 1
mkdir git
mkdir backup
cd ..
}
function s4_create_6_files(){
touch projects/linux{1,2}_{centos,redhat,c_programming}
}
function s5_make_directories_in_git(){
mkdir projects/git/linux1 projects/git/linux2
}
function s6_move_files_to_dir_1_or_2(){
mv projects/linux1_* projects/git/linux1/
mv projects/linux2_* projects/git/linux2/
}
function s7_create_package_and_compress(){
cd projects || exit 1
 tar -czvf backup/git.tar.gz git/
cd ..
}
function s8_delete_dir_git(){
rm -rf projects/git/
}
function s9_recover_from_git_tar_gz_backup(){
tar -zxvf projects/backup/git.tar.gz -C ./projects/
}
function s10_create_package_and_compress(){
cd projects || exit 1
tar -jcvf backup/git.tar.bz2 git/
cd ..
}
function s11_find_and_sort_alphabetically_all_created_files_and_dirs(){
	find ./projects \( -type f -o -type d \) | sort
}
function s12_get_next_15_minutes_boundary(){
	current_timestamp=$(date +%s)
	
	

	next_interval_timestamp=$(( ( (current_timestamp + 899) / 900 ) *900 ))
	next_15min_boundary=$(date -d @"$next_interval_timestamp" "+%Y-%m-%d %H:%M:%S")
	echo "$next_15min_boundary"
}
